Our NIR spectra cover the HeI 1.0833 \(\) m triplet. This feature can serve as a tracer of high velocity winds around RCB and dLHdC stars. The levels of this transition are 20 eV above the ground state, and cannot be populated by photospheric radiation of dLHdC and RCB stars. Instead, they can be collisionally excited in high velocity winds around these stars. The HeI feature has been observed in several RCB stars either as blueshifted absorption or with a P-Cygni profile with velocities as high as 500 km s\(^{-1}\)  [1]}, [2]}, [3]}. The strength and velocity of the winds around RCB stars are greatest when the star has just emerged from a dust enshrouded minimum, and decrease with time thereafter. This suggests that the winds around RCB stars are dust-driven; i.e. the gas is dragged to high velocities by dust grains that are accelerated by radiation pressure. As dLHdC stars do not show dust excesses in their spectral energy distributions, we do not expect to see dust-driven winds around them. [4]} observed the four previously known dLHdC stars and found no evidence for strong RCB-like HeI absorption lines in their spectra.
